1. Field of the Invention
The present invention relates to a porous metal oxide and a method of preparing the same, and more particularly, to a porous metal oxide having a particle shape that can be easily-controlled and pores having an adjustable shape and distribution, and a method of preparing the same.
2. Description of the Related Art
Porous metal oxides are used as electrode materials in the energy field. In general, electrode materials must have good electronic conductivity and good ionic conductivity, while ionic conductivity is typically lower than electronic conductivity. However, in porous electrode materials, ions can be delivered to the inside of the particles of the porous metal oxide, thereby reducing the distance that ions travel. Nano-materials may have similar effects as porous electrode materials, but have high contact resistance between the particles of the nano-materials and it is difficult to manufacture electrodes formed of nano-materials. Therefore, practical application of nano-materials is difficult.
Examples of porous metal oxides used as electrode materials include MnO2, LiCoO2, LiNiO2, LiCO1/3Ni1/3Mn1/3O2 which are used as cathode materials for lithium secondary batteries. In electrochemical capacitors, RuO2, NiO, etc. are used as pseudocapacitance materials. Porous metal oxides can also be used as electrode materials for solid oxide fuel cells (nickel oxide or cobalt oxide), molten carbonate fuel cells, borohydride fuel cells, or dye sensitized solar cells (titanium oxide).
Such porous metal oxides are typically prepared by a sintering method or a template method. Sintering is most frequently used to prepare porous metal oxides. It is difficult to prepare porous metal oxides in the form of a powder. To form the porous metal oxide in a predetermined shape, pressure molding can be performed.
A template method is frequently used for preparing porous materials having mesopores with a diameter of 50 nm or less. However, processing costs of the template method are high and mass production is difficult.